Human fluid pumping apparatus



Nov. 19, 1968 c. P. E. VON WRANGELL E AL 3,411,448

HUMAN FLUID PUMPING APPARATUS Filed April 14, 1967 2 Sheets-Sheet 1 11 2 4g. 1 15 56 C D 15 g m} A B 16 2 j i 12 i 14 l T m gg 4/ A 34 625:: $3.11 Ff] i l/ (I 5 I 42 40 INVENTORS'. Charles V0): Wrameli /h'chan? C Tat/(er flenrz 0. Vi [buck v & flTTOR/VWS 171012105 17 He ms Nov. 19, 1968 c. P. E. VON WRANGELL ET AL 3,411,448

HUMAN FLUID PUMPING APPARATUS Filed April 14, 1967 2 Sheets-$heet 2 MOTOR gNvENToRs. Clznr Zes' Von Wrangell United States Patent ABSTRACT OF THE DISCLOSURE A pumping apparatus for a body fluid carried system wherein human fluid is removed from one position of the body and infused into the body at .a second position. The pump comprises a compressible chamber compressed by a cam operated reciprocating rod on which is located an adjustable force means for maintaining a counterforce on the chamber.

Background of the invention This invention has particular .application to a pumping apparatus in a system for removing the human fluid from one position of the body and infusing the fluid into the body at a second position. In the process of removing and infusing the human fluid, it is necessary to cause the fluid to be removed under a pressure which is compatible with the body functions. In order to provide such conditions in the handling of a hum-an fluid, there has been .a need for a pump or other means for removing and transferring a human fluid outside the body safely and efficiently without any destruction or harm to the parts of the body from which the fluid may be removed and into which the fluid may be infused. According to the present invention, such a pumping apparatus is provided which can be adjusted to remove and transfer the different human fluids under various conditions compatible with the natural functions and characteristics of the body. That is, the pumping apparatus according to this invention, may safely remove a human fluid from the body at any predetermined position and transfer and cause the fluid to be infused into a second position of the body under pressures and flow rates completely compatible with the natural body functions at the respective removal and infusion positions of the body.

In the past, there have been several pumping apparatus or other means which could effect the removal and the infusion of certain human fluids, such as the lymph fluid, of the body. The main disadvantage of those pumping apparatus, is that they could not completely regulate the removal and transfer of the various human fluids according to the requirements of the natural body functions, and therefore, could only be used for the handling of certain fluids. Hence, there has been a need for a pumping apparatus that could be adjusted to regulate the conditions under which various human fluids could be removed from the body safely and effectively. Such a pumping apparatus is provided by the present invention, which is completely adjustable to regulate the conditions under which various human fluids can be removed from the body and infused thereinto.

The pumping apparatus according to this invention can effectively handle various human fluids under the required conditions of the body by virtue of the arrangement and structure of its component parts. The function and importance of each component part of the improved pumping apparatus are described in the description of the preferred embodiments hereinbelow.

3,411,448 Patented Nov. 19, 1968 ice Summary of the invention According to our invention, an improvement is provided in a pumping apparatus for a body fluid carried system wherein a human fluid is removed from one position of the body and infused into the body at a second position. Such human fluid being characterized by a natural availability determined by the natural body functions and flowing at an average rate and under a pressure limit to safely maintain flow thereof. The pumping apparatus has an elastic collapsible chamber for removing and holding a volume of the human fluid. The chamber having an inherent and limited elasticity to expel the fluid when compressed and to create therein an elastic force proportional to the degree that it is compressed. The elastic force is sufficient to inflate the chamber to cause a pressure to induce flow thereinto and to remove the human fluid from the body at the first position. The chamber having extend-ed therefrom a valved inlet and outlet. Positioned near the elastic chamber is provided compressing means to reciprocate to compress the chamber to expel the human fluid therefrom. Drive means are provided to actuate the compressing means to compress the chamber at a rate so that the fluid is expelled at a pressure compatible with the natural body pressure of the second body position. The improvement in the pumping apparatus comprises an adjustable force means for maintaining a counterforce on the chamber suflicient to adjustably regulate the rate at which the chamber expands to remove the fluid from the human body at the first body position at a pressure compatible with the natural body pressure of the fluid at such position. In addition, control means are provided for actuating the drive means only when the chamber is inflated.

In another aspect of our invention, the compressing means may be a freely reciprocal rod and the drive means includes in part a rotatable nutating cam surface to actuate the rod, with the adjustable force means acting directly on the rod to maintain the same always in contact with the elastic chamber. The adjustable force means may be a, torsion spring mechanism which constantly urges the rod toward the chamber to impose a counterforce on the chamber equal to the elastic force created therein.

According to another aspect of our invention, there is provided a lightweight portable pumping apparatus for use with a body fluid carried system wherein the human flllld is removed from one position of the body and infused into the body at a second position. Such fluid being characterized by a natural availability determined by the natural body functions and flowing at an average rate and under a pressure limit to safely maintain flow thereof. The pumping apparatus comprises a support base, an elast1c collapsible chamber mounted on one end of the base for removing and holding a volume of the human fluid. The chamber having an inherent and limited elasticity to expel the human fluid therefrom when compressed and to create therein an elastic force proportional to the degree that it is compressed. The elastic force being suflicient to inflate the channel to cause a pressure to induce flow therein and remove the human fluid from the body at the first position. Extended from the chamber are a valved inlet and outlet. Positioned parallel to the base with one free end transverse to the surface of the chamber is a freely reciprocable push rod to compress the chamber to expel the human fluid therefrom. Adjustable force means are provided for maintaining a counterforce on the chamber suflicient to adjustably regulate the rate at which the chamber expands to remove the fluid from the human body at the first position at a pressure compatible with the natural body pressure of the fluid at such position. Mounted on the base adjacent to the other free end of the push rod are drive means to actuate the push rod to compress the chamber at a rate so that the fluid is expelled at a pressure compatible with the natural body pressure of the second body position. Control means are provided for actuating the drive means only when the channel is inflated. The adjustable force means may be a torsion spring mechanism which constantly acts on the rod to maintain the contact of the rod with the elastic chamber. The drive means may include in part a nutating cam surface positioned adjacent to the other free end of the rod, whereby one rotation of the cam actuates the rod sufficient to compress the chamber.

In another aspect of our invention, there is provided a lightweight portable pumping apparatus for use in a fluid carried system wherein a fluid is transferred from one position to a second position under predetermined conditions of pressure and rate. The apparatus comprises an elastic collapsible chamber for holding a volume of the fluid. The chamber having an inherent and limited elasticity to expel the fluid when compressed and to create therein an elastic force proportional to the degree that it is compressed. The elastic force being sufiicient to inflate the chamber to cause a sufiicient pressure to induce flow therein and transfer the fluid from the first position. Extended from the chamber are a valved inlet and outlet. Positioned near the elastic chamber are compressing means to reciprocate to compress the chamber to expel the fluid therefrom. Adjustable force means are provided for maintaining a counterforce on the chamber suflicient to adjustably regulate the rate at which the chamber expels to remove the fluid from the first position at a predetermined pressure. Drive means are provided to actuate the compressing means to compress the chamber at a rate so that the fluid is expelled at a predetermined pressure suflicient to transfer the fluid to the second position. Control means are provided for actuating the drive means only when the chamber is inflated.

Other features and advantages of the present invention will; be more apparent from the description hereinbelow of the best mode contemplated for carrying out the invention.

Description of the drawings FIGURE 2 is a side elevational view of the pumping apparatus illustrated in FIG. 1 with the plunger advanced;

FIGURE 3 is a side elevational view of the pumping apparatus illustrated in FIG. 1 with the push rod held against the elastic chamber by the adjustable force means of this invention; and

FIGURE 4 is the electric circuitry of the present invention.

Description of the preferred embodiments Referring to FIGS. 1 to 3, a pumping apparatus embodying the present invention is shown. The apparatus in its general arrangement comprises a base which has mounted at one end an elastic collapsible chamber 11. Extended from the chamber 11 are a valved inlet 12 and an outlet 14. Compressing means, such as a freely reciprocal push rod 16 is slidably mounted on two supports 18 parallel to the base 10 with a free end near the chamber 11. The push rod 16 is caused to move toward the chamber 11 (to the left) by the rotation of a nutating cam surface 22 driven by a motor 24 through a shaft 25. The nutating cam 22 can be generally described as a truncated cylinder which is rotated about the longitudinal axis of the cylinder.

Mounted on a block 26 positioned on the base is an adjustable force means, shown here as a torsion spring 28. The spring 28 is U-shaped, and the two legs of which bear against two rollers A, which are disposed on opposite sides of rod 16 and mounted in a block B which is adjustably mounted on the push rod 16. The spring 28 by bearing against the rollers A, acts directly on the push rod 16, thereby maintaining the rod 16 always in contact with the elastic chamber 11.

Extended from the push rod 16 on the end of an arm 32 is a magnet 34. The arm 32 is adjustably mounted on the rod 16 by a clamp 36. When the magnet 34 is positioned over a normally opened reed switch 38, the circuit of the motor 24 is closed (FIG. 4), thereby starting the motor 24 to rotate the cam 22. The rotation of the cam 22 in turn causes the push rod 16 to move forward to the left to compress the chamber 10, as shown in FIG. 2. A second reed switch 40 is provided to keep the motor in operation until the cam 22 completes one revolution. When the cam 22 completes one revolution, the normally closed second switch 40 is opened by the magnet 42 on the cam 22 positioned over it, FIG. 3. Thus, no current can pass to the motor 24 and it stops almost immediately due to the braking action of the indicating lamps 44, as shown in FIG. 4. The function of indicating lamps 44 is described more fully hereinbelow.

The pumping apparatus illustrated in FIGS. l-3 and described herein may be used in a body fluid carried system wherein the human fluid is removed from one position of the body at a second position. The fluid is characterized by a natural availability determined by the natural body functions and should be caused to flow at an average rate and under a pressure limit to maintain safe flow thereof. Such a system is disclosed in the co-pending application having Ser. No. 641,085, filed Apr. 7, 1967.

As shown in FIGS. 1-3, the chamber 11 may be an elastic dome-shaped chamber having extended therefrom a valved inlet 12 and a valved outlet 14. Both the inlet 12 and outlet 14 are normally closed, and they may be elastic. The valved inlet 12 and outlet 14 are adapted to have connective tubing extending therefrom. Such tubing is intended to form a fluid-tight connection with the body at a removal position and an infusion position thereof.

The chamber 11 should be made of such material as to have an inherent and limited elasticity to expel a human fluid therein when compressed and to create therein an elastic force which is proportional to the degree that it is compressed. The elastic force shoud be suflicient to inflate the chamber 11 to cause a pressure to induce flow thereinto and remove the human fluid from the removal position (not shown) of the body.

The normal position of the chamber 11 is fully extended as shown in FIG. 1. The chamber is compressed by the movement of the push rod 16 is to the left as shown in FIG. 2. The push rod 16 is caused to move to the left by rotation of cam 22 driven by the motor 24 through a shaft 25. As the push rod 16 compresses the chamber 11, the compression simultaneously shuts the valved intake 12 and expels the fluid in the chamber 11 through the valved outlet 14. If the push rod 16 were reacted, the chamber 11 would be free to expand elastically to its normal position, limited only by the pressure admitted through the inlet 12 which has tubing connected to the removal position of the body, for example, the thoracic duct (not shown). However, by having the torsion spring 28 urge the rod 16 toward the chamber 11 by pressing against the rollers A, mounted thereon, a counter-force is maintained on the chamber 11 suflicient to adjustably regulate the rate at which the chamber 11 expands due to the elastic force created therein. By virtue of the adjustability of the counter-force on the elastic chamber 11 the fluid may be removed from the body at the removal position at a pressure that is compatible with the natural body pressure of the fluid in any particular patient at such position.

The elastic force of the diaphragm chamber is greatest when the diaphragm is fully compressed, FIG. 2. For

example, a silastic diaphragm of about one and a quarter (1%) inches diameter can be fully compressed with the stroke of about one-third inch of the push rod 16 which creates a force therein of about 1.6 pounds per square inch when so compressed. Accordingly, the elastic force created in the chamber diminishes as the chamber 11 is allowed to expand and is zero when the elastic chamber 11 has regained its fully expanded position; FIG. 1.

The cam 22 has a nutating surface which during a rotation causes the push rod 16 to move a certain distance which is sufficient to fully compress the chamber 11, thereby releasing the fluid therein. The push rod 16 does not return after the cam 22 has completed a rotation, but is held in contact with the chamber 11 by the torsion spring 28 and is caused to return its original retracted position only when and as the chamber 11 is inflated; FIG. 1.

The U-shaped spring 28 is adjustable and may be arranged to apply balance the elastic force of the chamber 11 to provide a fluid removal pressure compatible with that of the human fluid at the removal position of the body. As shown in FIGS. 1-3, the two legs of the U are forced backward into an arc and bear against the two roller-s A, which are mounted by pins C on the block B secured to the push rod 16 by a set screw D. When the push rod 16 is fully retracted (FIG. 1) the legs of the spring 28 are bent back into a nearly horizontal position and thus bear against the bottoms of the rollers A. The spring force is thus directed =upward, thus applying practically no force horizontally to oppose the elastic force of the chamber 11. Conversely, when the push rod 16 is fully advanced (FIG. 2) the legs of the U-shaped spring 28 bear against the rollers A so as to exert a more nearly horizontal force on the push rod 16. When the push rod 16 is in this fully advanced position, the spring 28 exerts a greater counterbalance force against the diaphragm 11. Although the spring 28 is actually bent through a large arc when the push rod 16 is fully retracted, the horizontal component of force provided by sprin 28 reaches a maximum net value when the push rod 16 is in its advanced position (FIG. 2), and this force diminishes as the push rod is brought back to its fully retracted position; FIG. 1. Thus, the push rod 16 exerts a force at all times equal and opposite to the elastic force of the chamber 11.

A very important feature of the counter-balancing force provided by the spring 28, is that it can be adjusted so as to maintain a counter-force on the elastic chamber 11 sufficient to adjustably regulate the rate at which the chamber 11 expands to remove the fluid from the human body at a pressure compatible with the natural body functions at the removal position of the body. Thus, the removal of any fluid from the body can be accomplished safely without anyharm or destruction to the walls of the conduit from which the human fluid may be removed.

The counter-force exerted by the spring 28 can be adjusted in one of two ways. One way is by moving the spring support block 26 with respect to the base 10. The alternate way is by moving the roller block B with respect to the push rod 18.

As shown in FIG. 1 the block 26 can be moved to the right or left by turning an adjustment screw E, extending to the block. If the support block 26 is moved to the left, the spring 28 will be flat for a greater portion of the push rod 16 travel, and, thus, a horizontal counterforce component of the spring 28 force will be decreased. Conversely, the shifting of the block 26 to the right will cause the spring 28 to bear against the rollers A so as to exert a more horizontally directed, and therefore stronger, counter-b alancing force.

Alternately, the counter-force of the spring 28 can be adjusted by moving the roller block B to the left or right along the push rod 16 by first loosing the set screw whatever force is necessary to counter- 6 D; FIGS. 1-3. If the block B is shifted to the left (toward the chamber 11) the spring 28 will bear against the rollers A with a more horizontally directed force. If the block B is positioned more to the right (toward the cam 22) the spring 28 will bear upon the rollers A with a force directed upwards for a greater portion of the plunger travel, and therefore the counter-force opposing the chamber expansion will be less.

As can be seen, by increasing or decreasing the counterbalance force of the spring, as described above, the expansion rate ofthe elastic chamber 11 can be regulated at any rate required for the safe removal of a human fluid from :any part of the body. In other words, by regulating the rate of expansion of the chamber 11 the pressure under which a fluid is removed can safely be maintained as required by the natural body functions.

Referring to FIG. 4, an electrical circuit is shown which may be used for the controlled operation of the pumping apparatus. The respective reed switches 38 and 40, the motor 24 and the indicating lamps 44 with the connective wiring are shown in their relative positions. There may be one or more indicator lamps 44 connected in circuit across the motor terminals which serve the function of quickly stopping the motor. Thus, when the source of electrical power is shut off by the opening of the normally closed reed switch 40 under the influence of the magnet 42 carried by the cam 22, the indicator lamps 44 hasten the stoppage of the motor by producing a dynamic braking action. That is, the coasting motor m0- mentarily acts as a generator and the indicator lamps 44 are an electrical load causing the rotational energy to be quickly dissipated, bringing the motor 24 to an almost immediate stop. The normally opened switch 38 is closed when the magnet 32 is brought over it while the second reed switch 40 which is normally closed is opened when the magnet 42 is directly over it; FIG. 1.

The power to operate the pumping apparatus may be derived from any source, such as a battery or an electrical output. It is preferred, however, that the power be supplied by a battery since the pumping apparatus is intended to be portable, i.e., Worn by the patient. All that is necessary is that the power be available on demand when the pumping apparatus is to be put in operation to transfer a human fluid as required by the natural body functions.

Although the various features of the invention have been shown as applied to several embodiments of the invention, it will be evident that changes may be made in such details and certain features may be used without departing from the principles of the invention.

We claim:

1. In a pumping apparatus for a body fluid carried system wherein a human fluid is removed from one position of the body and infused into the body at a second position, such fluid being characterized by a natural availability determined by the natural body functions and flowing at an average rate and under a pressure limit to safely maintain flow thereof; wherein said pumping apparatus has:

(a) an elastic collapsible chamber for removing and holding a volume of said human fluid, said chamber having an inherent and limited elasticity to expel said fluid when compressed and to create therein an elastic force proportional to the degree that it is compressed, said elastic force being sufficient to inflate the chamber to cause a pressure to induce flow thereinto and remove said human fluid from said body at said first position, said chamber having extended therefrom a valved inlet and outlet;

(b) compressing means positioned near the elastic chamber to reciprocate to compress said chamber to expel the human fluid therefrom; and

(c) drive means to actuate said compressing means to compress the chamber at a rate so that said fluid is expelled at a pressure compatible with the material body pressure of said second body position; wherein the improvement comprises:

(i) adjustable force means for maintaining a counterforce on said chamber suflicient to adjustably regulate the rate at which said chamber expands to remove said fluid from said human body at said first body position at a pressure compatible with the natural body pressure of said fluid at such position; and control means for actuating said drive means only when said chamber is inflated.

2. A pumping apparatus according to claim 1, wherein said compressing means is a freely reciprocable push rod and said drive means includes in part a rotatable nutating cam surface to actuate said rod, with said adjustable force means directly acting on said rod to maintain the same always in contact with said elastic chamber.

3. A pumping apparatus according to claims 1 and 2 wherein said adjustable force means is a torsion spring mechanism which constantly urges said rod toward said chamber to impose a counterforce on said chamber equal to said elastic force.

4. A lightweight portable pumping apparatus for use in a body fluid carried system wherein a human fluid is removed from one position of the body and infused into the body at a second position, such fluid being characterized by a natural availability determined by the natural body functions and flowing at an average rate and under a pressure limit to safely maintain flow thereof, said pumping apparatus comprising:

(a) a support base;

(b) an elastic collapsible chamber mounted on one end of said base for removing and holding a volume of said fluid, said chamber having an inherent and limited elasticity to expel said human fluid therefrom when compressed and to create therein an elastic force proportional to the degree that it is compressed, said elastic force being sufficient to inflate the chamber to cause apressure to induce flow thereinto and remove said human fluid from said body at said first position, said chamber having extended therefrom a valved inlet and outlet;

(c) a freely reciprocable push rod positioned parallel to said base with one free end transverse to the surface of said chamber to compress the chamber to expel the human fluid therefrom;

(d) adjustable force means for maintaining a counterforce on said chamber suflicient to adjustably regulate the rate at which the chamber expands to remove the fluid from said human body at said first position at a pressure compatible with the natural body pressure of said fluid at such position;

(c) drive means mounted on said base adjacent to the other free end of said push rod to actuate said push rod to compress the chamber at a rate so that said fluid is expelled at a pressure compatible with the natural body pressure of said second body position; and

(1?) control means for actuating said drive means only when said chamber is inflated.

5. A pumping apparatus according to claim 4, wherein said adjustable force means is a torsion spring mechanism directly acting on said rod to maintain the same always in contact with said elastic chamber.

6. A pumping apparatus according to claim 4, wherein said driving means includes in part a nutating cam surface positioned adjacent to said other free end of said rod, said nutating cam surface in one rotation actuates said rod sufficient to compress said chamber,

7. A pumping apparatus according to claims 4 and 6, wherein there is included a second control means to cause said mutating cam to rotate only once when said elastic chamber is partially inflated.

8. A pumping apparatus according to claim 4, wherein said adjustable force means is a U-shaped torsion spring adjustably mounted on said support base with its tWO legs bearing on opposite sides of the push rod to maintain said rod always in contact with said elastic chamber.

9. A lightweight portable pumping apparatus for use in a fluid carried system wherein a fluid is transferred from one position to a second position under predetermined conditions of pressure and rate, said apparatus comprising:

(a) an elastic collapsible chamber for holding a volume of said fluid, said chamber having an inherent and limited elasticity to expel said fluid when compressed and to create therein an elastic force proportional to the degree that it is compressed, said elastic force being sufficient to inflate the chamber to cause a pressure to induce flow therein and transfer said fluid from said first position, said chamber having extended therefrom a valved inlet and outlet;

(b) compressing means positioned near the elastic chamber to reciprocate to compress said chamber to expel the fluid therefrom;

(c) adjustable force means for maintaining a counterforce on said chamber suflicient to adjustably regulate the rate at which said chamber expels to remove the fluid from the first position at a predetermined pressure;

((1) drive means to actuate said compressing means to compress the chamber at a rate so that said fluid is expelled at a predetermined pressure sufiicient to transfer said fluid to said second position; and

(e) control means for actuating said drive means only when the chamber is inflated.

References Cited UNITED STATES PATENTS ROBERT M. WALKER, Primary Examiner. 

